OK, well my idle has been screwy since i installed my injectors. I kept thinking that my UIM to LIM gasket wasnt sealing so i redid it 3 times. Finally i was VERY confident it was sealed, and wasnt worried about it, but my idle was still around 1500 and pulsing. SO...i starting looking for where unmetered air was getting in...

My BAC valve gasket was leaking so i made a new gasket for that...seemed to get rid of some of the pusle but even with the idle set as low as possible using the BAC it was at 1200-1400.

SO i looked at my intake. (1300CC.com Turbo II TID mod) - i have an S4 and that is for an S5 so it was a bit different...not much but the only problem was that the AFM was not 3 inch diameter going toward the turbo so the 3 inch fitting i bought didnt fit right. i finally was able to seal it using silicone and some hose clamps, but my idle still wasnt right.

I had adjust my TPS a while back, so i wasnt worried about that at all.

THEN i noticed that if its idling high i can bog it down by letting the clutch out...then when i put the clutch back in it stays at a good smooth idle around 900....which makes me think the TPS must be off because the IDLE can be there...just isnt set there itself.

Should i just go in an adjust the TPS, or is there something else to look at??? its snowy today so i couldnt do anything to it, but tomorrow i will have a bit of time before work...enough to at least adjust the TPS (i have about 10 minutes at home before i have to leave for work....)

anything else to look at? certain vac lines that might cause this? other gaskets?

i know it may not be THAT specific but any help would be appreciated.

Thanks,
-Matt

 

ANYONE??? please....

 

how "able" were you to seal it with silicone?

because Id say thats part of, or the cause of, your idle trouble

 

well...it was sealed well enough that the car did idle fine before....ive only had idle troubles since swapping out secondary injectors. the car seems like its acting funny all around though. when i tap the gas lightly while cruising it jerks forward a bit, then goes like normal, and when using cruise control it jerks a lot...especially on downhills...

and....seems like it accelerates weird while cold...until i drive it for at least 5 minutes (after warming up for 5 as well)

 

Matt any luck? My NA recently has had a similar problem where my idle sticks around 1500 and sometimes pulsates, but I can use my clutch to get it down to around 750. I don't understand this. Is it probably a bad TPS? Like you said my car is capable of a good idle but doesn't do it on its own. So what causes it to "decide" to stay at 1500? Even when it is at 1500 I try playing with the throttle body and it seems like the butterflies are closed.

 

pulsing idle usually is caused by an improper TPS adjustment.

 

Totally TPS, mine does the same thing. Its pretty much that your TPS take a minute to "stabilize" its reading, and until the confuses the ECU to all hell.